LONDON (AP) — A U.S. congressman says the bomb used in the deadly Manchester Arena attack in England suggests a “level of sophistication” that might indicate its maker had foreign training.

Texas Republican Mike McCaul, chairman of the House Homeland Security Committee, told The Associated Press on Wednesday that the bomb that killed 22 people and the alleged attacker was “a classic explosive device used by terrorists.”

McCaul said the device used the explosive TATP, the same one used in the deadly November 2015 attacks in Paris and the March 2016 attack in Brussels carried out by Islamic State extremists.

McCaul was due to get an intelligence briefing on the Manchester attack later Wednesday.

He says the evidence so far suggests “we’re not dealing with a lone wolf situation.”

Echoing the comments of British officials, he said: “There’s a network — a cell of ISIS-inspired terrorists.”